This invention relates to folding and binding paper and other sheet media by reactivating the same imaging material, toner, ink and the like, used to print the text or images on the sheets.
Devices for folding and binding media sheets to form mailable letters, pamphlets, and similar documents from a single sheet are known in the art. These mailable letters are sometimes referred to as xe2x80x9cself mailers.xe2x80x9d Conventional devices for making self mailers typically use a buckle chute folder in conjunction with an adhesive applicator and/or a moistener that activates adhesive previously applied to the sheet. Such devices often require specialized paper and the user must replenish exhausted adhesive applicators and moisteners. Conventional devices are unable to operate at the speed of modern laser printers and other image forming devices, requiring additional time for adhesive application and curing. The strength of the seal is controlled only by the type of adhesive used. Moreover, due to the necessary placement of the adhesive applicators and moisteners, adhesive residue is transferred to the components of the folding mechanism during operation. Consequently, components of the device must be coated, plated or otherwise safeguarded against adhesive build-up. Many adhesives exhibit aging problems as they deteriorate over time and the ambient environment in which they are applied often must be controlled to assure proper adhesion.
The present invention is directed to devices and methods for folding and binding sheet media using imaging material as the binder. The invention combines the binding techniques described in my copending application Ser. No. 09/320,060 titled Binding Sheet Media Using Imaging Material with a buckle chute type folding device to form self mailers and other types of folded and bound or sealed documents. The invention reduces the binding xe2x80x9cmaterial mixxe2x80x9dxe2x80x94only paper and toner is necessaryxe2x80x94to alleviate many of the problems associated with conventional adhesive type binders. Also, the need for staples, clips, spirals and other types of mechanical binders is reduced or eliminated. This helps reduce cost and minimize difficulties recycling or otherwise salvaging used documents.
In one apparatus embodiment of the invention, the device for folding and binding sheet media includes a buckle chute, a binder downstream in the paper path from the buckle chute, an input driver proximate to and upstream from the buckle chute, and an exit driver proximate to and between the buckle chute and the binder. The input driver directs the media sheet into the buckle chute and, in cooperation with the buckle chute, buckles the media sheet along a fold line. The exit driver receives the sheet from the buckle chute, folds the sheet along the fold line and directs the sheet towards the binder. The binder then reactivates imaging material applied to the binding region of the media sheet using the toner fusing or other techniques described in the ""060 application.
It is expected that the folder will usually include multiple buckle chutes and an intermediate driver between buckle chutes. A bi-fold three panel document, for example, uses two buckle chutes, an input driver, one intermediate driver and an exit driver. Rollers are typically used for the drivers. In one version of the drivers, the input driver includes first and second rollers forming a first nip therebetween through which the media sheet is directed into the first buckle chute. The intermediate driver includes the second roller and a third roller forming a second nip therebetween through which the media sheet is received from the first buckle chute, folded and directed to the second buckle chute. The exit driver includes the third roller and a fourth roller forming a third nip therebetween through which the media sheet is received from the second buckle chute, folded and directed to the binder.
In one method embodiment of the invention, imaging material is applied to a media sheet in the pattern of a desired print image to a binding region on the sheet, the imaging material is activated in the print pattern and in the binding region, the sheet is folded into two or more panels, and the imaging material is then reactivated in the binding region to bind the panels together.